DSA Visualizer
Stack vs queue, step by step
Same operations, opposite order. A stack hands back the item you added most recently; a queue hands back the one that has been waiting longest.
A fixed demo sequence: push A, B, C — pop — push D — pop, pop. Watch which item leaves each time.
Empty
Step 1 of 8
Empty stack. Last in, first out (LIFO): the most recently pushed item is the first one popped — like a stack of plates.
Put this into practice
Connect the idea to a worked lesson, a practical task or your interview preparation.
- Concept guideStacks and Queues →Two disciplined ways to restrict how you add and remove items: last-in-first-out, and first-in-first-out.
- Practice problemBalanced Parentheses →Solve this easy problem with samples, hints and checks in your browser.
- Practice problemWarmer Day Countdown →Solve this medium problem with samples, hints and checks in your browser.
- Interview prepCoding & DSA interview questions →The concepts behind data-structure and algorithm interview questions — paired with the practice problems that let you actually write the code.
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